<!DOCTYPE html> 
<html class="reftest-wait">
<body>
<div id="d" style="opacity:0.9; height:10px;">
  <div style="position:absolute; top:100px; width:200px; height:200px; background:lime"></div>
</div>
<script>
var d = document.getElementById("d");

function doTest() {
  d.style.opacity = 0.8;
  setTimeout(function() {
    d.style.opacity = 0.5;
    document.documentElement.removeAttribute("class");
  }, 50);
}
window.addEventListener("MozReftestInvalidate", doTest, false);
</script>
</body>
</html>
